I am a radio producer interested in trying out my iPhone 4s for professional recording as a backup for my dedicated recorder. I'll mostly be using this to record panel discussions and presentations from a mixing board; I need the capability to record line level and mic level. I've looked at a lot of interfaces, some that plug into the dock connecter and have an ADC and others that plug into the analog 3.5mm jack on the iPhone. Like the Mobile In, all of the digital/dock adapters advertise generally better sound quality and a superior ADC to the the one onboard the iPhone.

But I haven't been able to find the resolution specs for the 4s codec--does anyone know what they are? If not, what specifically makes the Mobile In ADC superior to that in the iPhone? Or is it the dock connection that's more significant to improving recording quality? Something else?

Ultimately the iOS audio codec is going to dictate what quality the audio files are encoded at. At the same time, the quality of the audio conversion can only go as high of a resolution as the hardware can support. So even if the iOS codec could do say 192 kHz, you still would be limited by the codec used by the hardware to input the signal.

I was unable to find specs for Apple's iOS 5.0 core audio codec at this time, however the Mobile In is capable of encoding audio up to 24-bit/48 kHz. So essentially you can ensure that the Mobile In can encode up to those specs if the current iOS audio codec is capable of it.

What does it even mean to say the guitar input has 11dB dynamic range? I don't believe it could possibly be that low. That is probably the worst dynamic range spec I have ever seen anywhere: I think 78RPM records could beat it!

Could you check with the techies and give us some real numbers?

The information above may not be current, and you should direct questions to the current forum or review the manual.